The present invention relates to analog-to-digital conversion circuitry and, more particularly, to an analog-to-digital converter useful for dual slope (double integral) operation where an off-set voltage inherent to an operational amplifier for an integrator can be canceled by mathematical calculation.
In the conventional analog-to-digital converter circuit, the off-set voltage caused errors in determining a measured voltage. Several further problems arise in connection with the analog-to-digital conversion system, especially when combined with computer system.